Flexible debulking catheters with imaging and methods of use and manufacture

Abstract

Catheters and methods for removing material from (or “debulking”) a body lumen while imaging the region comprised of the material are provided. The catheters can be used in body lumens, including but not limited to intravascular lumens such as coronary or peripheral arteries. The catheters include housings or other structures to mount or protect an imaging transducer. Generally, debulking catheters include a proximal portion, a distal portion having an opening, a cutting element which may be exposed through the opening to contact material in a body lumen and an imaging transducer with associated circuitry and display. The catheter debulks a body lumen when it is moved while the cutting element is in contact with the material in the lumen and the region comprised of the material is imaged before, after, or during catheter movement.

What is claimed is: 
     
       1. A catheter for deployment in a vessel comprising:
 a control handle; 
 an elongate proximal segment having proximal and distal ends, the proximal end being connected to the control handle; 
 a distal tip assembly having proximal and distal ends; and 
 a housing having a proximal end portion comprising a first material, a distal end portion comprising a second material, and a body portion extending between the proximal and distal end portions, the body portion comprising a third material, the first and second materials being different from the third material, the proximal end portion being connected to the distal end of the elongate proximal segment, the distal end portion being connected to the proximal end of the distal tip assembly, the housing having a luminal wall with an inner surface defining a lumen, the luminal wall having at least one slot; 
 a transducer mounted at least partially within the lumen of the housing; and 
 a first tubular member having proximal and distal ends and a wall defining a lumen, at least a portion of the first tubular member being positioned within the lumen of the housing and being connected to the proximal end portion of the housing, wherein at least a portion of the transducer is disposed within the lumen of the first tubular member. 
 
     
     
       2. The catheter of  claim 1  wherein an outer surface of the housing has at least one longitudinally extending rib. 
     
     
       3. The catheter of  claim 2  wherein the at least one longitudinally extending rib on the outer surface of the luminal wall is in the range of 5 to 8 ribs. 
     
     
       4. The catheter of  claim 1  wherein the at least one slot in the luminal wall is two slots. 
     
     
       5. The catheter of  claim 1  wherein the transducer is at a position spaced from the luminal wall to form a gap between the transducer and the luminal wall. 
     
     
       6. The catheter of  claim 1  wherein the transducer is configured to have 360° image capability of the vessel through the luminal wall of the housing and through the at least one slot of the housing, a radial angle of the circumference of the housing imaged by the transducer through the at least one slot in the luminal wall of the housing is in the range of 60° to 180°. 
     
     
       7. The catheter of  claim 6  wherein the radial angle is in the range of 120° to 150°. 
     
     
       8. The catheter of  claim 7  wherein the radial angle is 130°. 
     
     
       9. The catheter of  claim 4  wherein the transducer is configured to have 360° image capability of the vessel through the luminal wall of the housing and through the at least one slot of the housing, radial angle of the circumference of the housing imaged by the transducer through each slot in the luminal wall of the housing is in the range of 60° to 180°. 
     
     
       10. The catheter of  claim 9  wherein the radial angle is in the range of 65° to 90°. 
     
     
       11. The catheter of  claim 10  wherein the radial angle is 73°. 
     
     
       12. The catheter of  claim 1  wherein the first and second materials comprise metal and the third material comprises polymer. 
     
     
       13. The catheter of  claim 12  wherein the first material comprises stainless steel, the second material comprises tungsten and the third material comprises acrylonitrile butadiene styrene (ABS). 
     
     
       14. The catheter of  claim 12  wherein the distal end of the elongate proximal segment connected to the proximal end portion of the housing comprises stainless steel. 
     
     
       15. The catheter of  claim 1  wherein a proximal portion of the first tubular member extends proximally from the proximal end of the housing within a lumen in the elongate proximal segment such that the proximal end of the first tubular member is proximal of the distal end of the elongate proximal segment. 
     
     
       16. The catheter of  claim 1  further comprising: a second tubular member having proximal and distal ends and a wall defining a lumen, at least a portion of the second tubular member being positioned within the lumen of the first tubular member, a distance between an outer surface of the wall of the second tubular member and an inner surface of the wall of the first tubular member defining a gap between the first and second tubular members; and wherein the transducer further comprises wires extending proximally to the control handle, the wires being positioned to extend through the gap between the first and second tubular members. 
     
     
       17. The catheter of  claim 1  wherein the distal end of the first tubular member is proximal of the slot in the housing. 
     
     
       18. The catheter of  claim 16  wherein the distal end of the second tubular member is positioned between the distal and proximal ends of the first tubular member and the proximal end of the second tubular member is positioned proximal of the proximal end of the first tubular member. 
     
     
       19. The catheter of  claim 1  wherein the distal end of the elongate proximal segment is connected to the proximal end portion of the housing by a weld. 
     
     
       20. The catheter of  claim 1  wherein the distal end portion of the housing includes opposing pin holes which are positioned to align with opposing pin holes in the distal tip assembly and wherein the catheter further comprises pins positioned in the aligned pin holes. 
     
     
       21. The catheter of  claim 16  further comprising a potting material contained within the gap between the first and second tubular members. 
     
     
       22. A catheter for deployment in a vessel comprising:
 a control handle; 
 an elongate proximal segment having proximal and distal ends, the proximal end being connected to the control handle; 
 a distal tip assembly having proximal and distal ends; and 
 a housing having a proximal end portion, a distal end portion, and a body portion extending between the proximal and distal end portions, the proximal end portion being connected to the distal end of the elongate proximal segment, the distal end portion being connected to the proximal end of the distal tip assembly, the housing having at least one slot; 
 a first tubular member having proximal and distal ends and a wall defining a lumen, at least a portion of the first tubular member being positioned within the lumen of the housing and being connected to the proximal end portion of the housing; and 
 a transducer mounted at least partially within the lumen of the housing, at least a portion of the transducer being positioned within the lumen of the first tubular member, the transducer having image capability of the vessel through the at least one slot of the housing, the transducer including wires extending proximally to the control handle, 
 wherein the distal end of the first tubular member is proximal of the slot in the housing. 
 
     
     
       23. The catheter of  claim 22  wherein a proximal portion of the first tubular member extends proximally from the proximal end of the housing within a lumen in the elongate proximal segment such that the proximal end of the first tubular member is proximal of the distal end of the elongate proximal segment. 
     
     
       24. The catheter of  claim 22  further comprising:
 a second tubular member having proximal and distal ends and a wall defining a lumen, at least a portion of the second tubular member being positioned within the lumen of the first tubular member, a distance between an outer surface of the wall of the second tubular member and an inner surface of the wall of the first tubular member defining a gap between the first and second tubular members, the wires extending through the gap between the first and second tubular members. 
 
     
     
       25. The catheter of  claim 24  wherein the distal end of the second tubular member is positioned between the distal and proximal ends of the first tubular member and the proximal end of the second tubular member is positioned proximal of the proximal end of the first tubular member. 
     
     
       26. The catheter of  claim 24  further comprising a potting material contained within the gap between the first and second tubular members. 
     
     
       27. The catheter of  claim 1 , wherein the first tubular member comprises a rigid tube. 
     
     
       28. The catheter of  claim 22 , wherein the first tubular member comprises a rigid tube. 
     
     
       29. A catheter for deployment in a vessel comprising:
 a control handle; 
 an elongate proximal segment having proximal and distal ends, the proximal end being connected to the control handle; 
 a distal tip assembly having proximal and distal ends; and 
 a housing having a proximal end portion comprising a first material, a distal end portion comprising a second material, and a body portion extending between the proximal and distal end portions, the body portion comprising a third material, the first and second materials being different from the third material, the proximal end portion being connected to the distal end of the elongate proximal segment, the distal end portion being connected to the proximal end of the distal tip assembly, the housing having a luminal wall with an inner surface defining a lumen, the luminal wall having at least one slot; and 
 a transducer mounted at least partially within the lumen of the housing, 
 wherein the distal end of the first tubular member is proximal of the slot in the housing, 
 wherein the distal end of the second tubular member is positioned between the distal and proximal ends of the first tubular member and the proximal end of the second tubular member is positioned proximal of the proximal end of the first tubular member. 
 
     
     
       30. A catheter for deployment in a vessel comprising:
 a control handle; 
 an elongate proximal segment having proximal and distal ends, the proximal end being connected to the control handle; 
 a distal tip assembly having proximal and distal ends; and 
 a housing having a proximal end portion, a distal end portion, and a body portion extending between the proximal and distal end portions, the proximal end portion being connected to the distal end of the elongate proximal segment, the distal end portion being connected to the proximal end of the distal tip assembly, the housing having at least one slot; 
 a first tubular member having proximal and distal ends and a wall defining a lumen, at least a portion of the first tubular member being positioned within the lumen of the housing and being connected to the proximal end portion of the housing; and 
 a transducer mounted at least partially within the lumen of the housing, at least a portion of the transducer being positioned within the lumen of the first tubular member, the transducer having image capability of the vessel through the at least one slot of the housing, the transducer including wires extending proximally to the control handle, 
 wherein a proximal portion of the first tubular member extends proximally from the proximal end of the housing within a lumen in the elongate proximal segment such that the proximal end of the first tubular member is proximal of the distal end of the elongate proximal segment.